Rechargeable battery charging time vs. mA current calculator
Charging rechargeable batteries.
How long time does it take to recharge a rechargeable battery?
Type into the calculator your rechargeable battery’s capacity number, normally can be red on the battery body e.g. 1700 mAh ( milli-ampere-hours ). Then select the battery type/size in the left column ( NiMH - NiCd - AAA - AA - C - D - 9V ( 9 volt )) and in the right side select a current output ( electric power output ) of your charger in mA ( milli-ampers ).
Type in a capacity number of one battery only. Without changing outcome as per hours/mA a 1-4 batteries can be charged.
You can select and use a specific / special battery sizes at the bottom of the field and then set a different current output from a battery charger, if needed, by choosing the 1mA current and multiplying the outcome backwards - dividing in fact by the existing current value at which your charging equipment operates.
Re-charging 9 volt rechargeable batteries
Time control for charging of common 9V rechargeable batteries ( NiCd and NiMH 9 V batteries.) The timer takes longer because these can only be charged at much lower current rate of 0.1C or 1/10C ( mAhr/10 = charging time in hours ) of their mAh capacity value. Usually between 30 mA to 100 mA depending on the 9V battery capacity in mAh. This is still great to put up with considering that the 9 volts non rechargeable batteries cost arm and leg, but they don’t have to.
Trickle charge, continuous charging method
This is done with a very low charging current to keep the battery or batteries constantly alive, same like with a cordless phone baterry pack that is docked in its station base.
Common abbreviations - symbols - prefixes
nickel-metal hydride ( cell ) - NiMH
nickel-cadmium battery ( cells ) - NiCd
9 volts battery - 9V - 9 V
milliampere hour - mAh - mAhr - mAhrs
milliampere - mA ( 1/1000 of ampere )
ampere - A ( electric charge amount measure )
battery current or capacity - C
hour - h - hr
hours - hrs
How do I calculate charging time for rechargable battery manually ?
Formula for manual calculation for battery recharging processes
AAA - AA - C - D sizes rechargeable batteries: hours ( charging time ) equals to 12 x Ahr OR 12/100 x mAh ( 12/100 x mAh = hrs )
9v ( 9 volt ) rechargable batteries: hours equal to battery mAhr/10 ( mAh/10 = hrs )
Basics
battery charging time = capacity of the battery / charging current power output of the charger
hr = mAh / mA
This is great! I was looking for how to recharge aaa and aa size rechargeable batteries. Our very old charger died recently so I build provisionally a manual charger powered from a car battery, its current is 200 mA , I can connect this charger in the morning and switch off after work day. The batteries, 15 to 20 of them, 1.2V we use in remotes, mini maglite flashlights, 2 larger maglites, and etc. handy for around the house, all are very old, years old!
Battery type : 1600 mAh NiMH size AA rechargeable battery
Require : 9.6 hours of re-charging in 200 mA current output charger
Fraction : 9 3/5 hours of recharging at 200 mA current battery charger
Size AAA 170 mah 1.25V batteries ( 1.25 volt not 1.2 V ), can’t see any more on these whether they are nicd or nimh. But they still hold power perfectly even though I never discharged them before charging; only they are always pretty flat before they are placed into any charger:
Battery type : 170 mAh NiMH/NiCd size AAA rechargeable battery, Require : 1.0 hour of re-charging in 200 mA current output charger … that’s pretty right it took this long also in my old inteligent battery charger.
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I have 4 x 1750 mAhr ( milliampere hour ) each NiMH AA rechargable batteries and also using a simple-manual switch off with no timer built in 500 mA universal battery charger.
battery type : 1750 mAh NiMH size AA rechargeable battery, time = 4.2 hours to be fully recharged with 500 mA battery charger, fraction : 4 1/5 hour(s) to be fully charged by using 500 mA charger electric power current.
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I’ve been using 2 x size AA 2400 mAh and 4 x 2700 mAh capacity size AA batteries and can set my NiMH / NiCd battery chargers at up to 450 mA current output power. Usually I just recharge them when my radio, mini led light and large maglite, flashlight are flat. Meaning I never run discharge before charging as the batteries should be equal and are also charged in the same groups as they are being used. This is very practical calculator.
Cell type 2400 mAh NiMH size AA rechargeable battery
needs 6.4 hour(s) of re-charging in 450 mA current output charger
fraction - 6 2/5 hours of re-charging in 450 mA current output charge
Cell type 2700 mAh NiMH size AA rechargeble battery
needs 7.2 hour(s) of re-charging in 450 mA current output charger
fraction - 7 1/5 hours of re-charging in 450 mA current output charger
Battery type : 5000 mAh NiMH size D rechargeable battery, require : 14.5 hours of recharging with 450 mA current output charger, fraction : 14 1/2 hour(s) of recharging with 450 mA current output charger.
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Yesterday I was finding out how long does it take to recharge a aa battery. I am using a travel sort 350 ma 1.4V volt battery charger for 4x ni-mh AA type 2100 mah size batteries and, as it seems they have charged properly with the timing below.
Battery type : 2100 mAh NiMH size AA rechargeable battery. Require time : 7.20 hour(s) of re-charging in 350 mA current output charger. Fraction outcome : 7 1/5 hour(s) of re-charging in 350 mA current output charger.
The same charger charges 4x triple aaa size batteries at 150 ma power current and 9V type batteries at 30 ma output. I can say that I am quite happy about it; saving lots of money per each year, and the environment, instead of buying many alkaline non-rechargeable 1.5V batteries for personal and at home use. Thank you for this mAhr / mA versus charging time length battery calculator.
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How long to charge 2700mah batteries with 150ma charger? I need locate somewhere a more powerful electric transformer for my diode bridge to shorten this long charging time!
Battery type : 2700 mAh NiMH size AA rechargeable battery, Require : 21.6 hours of re-charging in 150 mA current output charger, Fraction : 21 3/5 hour for full recharging in 150 mA current power output charger.
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My charging time calculation of aaa nimh battery for remote controls around the house and type d large rechargeable batteries used in maglites and maglite flashlights I have. I was wondering whether it is all right or safe to be recharging 9 volts batteries for fire alarms?
Battery type 1100 mAh NiMH size AAA rechargeable battery, take 7.3 hours long time to be fully recharged with a 180 mA charger. Fraction : 7 3/10 hour to be fully recharged with charger with 180mA current power output.
Battery type 4700 mAh NiMH size D rechargeable battery, take 11.1 hours time of re-charging in a 550 mA current output charger. Fraction : 11 1/10 hour of recharging in 550mA current power output charger.
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Before I found this charging calculator I was facing the dilemma about how long does it take to recharge a aa battery, or, how long do aaa rechargeable batteries take to charge. So basically now I know how to set for any size of battery charging time and also how to choose the right power output, how long does it take till the batery charging process must be turned off to stop, and, a battery charger calculation.
Comment from/about : How long to charge rechargeable batteries for. | Permalink
I used this page to calculate recharge-able batteries charge time, specifically so charge time for 1.2 v 1100mah ni-mh and other 1.2volt aaa mah values rechargeable batteries, plus how long to charge 9volt battery for replacement in firealarm which I test on regular bases.
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This is perfect device to calculate charge time for ni-mh rechargeable aa ( and type aaa ) batteries for me and, was wondering what would be the time taken for aa rechargable batteries for charging in my 5 hour time preset 380ma strong charger, whether the timer limit should be enough or if not if I should double it - which is the case.
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I was looking for c code meaning or c symbol and how to use it in battery charging processes. I wanted to make sure that the C letter stands for the total capacity of the battery in mah milli-ampere hours - to be able to calculate manually how long does it take to charge a mah battery, with a question; how many hours do i charge a aa rechargeable battery?, but this calculator does it perfectly enough without having have to use pen and paper. Thank you, keep up doing the great work.
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… how long 4 aaa and also aa nimh charge for 1800 mah etc. plus charge rate ma calculate for choosing an appropriate charger, having one 300 milliampere transformer to use.
Battery type 1800 mAh NiMH size AA rechargeable battery, takes 7.2 hours to be fully recharged with using 300 mA charger. Fraction number 7 1/5 hour-s to be fully recharged in 300 mA battery charger.
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Any effect if I use 2 x 1600mah together with 2x 2800mah rechargeble GP batteries?
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charging time aaa
Quick to calculate nimh charge current power with charging time for aaa batteries involved.
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Excellent! I also needed calculation or a charger table with how many hours it takes to charge rechargeable batteries.
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Thanks for this rechargeable aa calculator. I looked for this info to know how long time to leave my old battery in an old charge we have at home. I found out had to double the time from what I practiced before. Now I’ve been using the battery for actually a couple or three of days more, which already is two days extra of it being used, like before, only longer! I believe the charging process taken this last time had to be much more accurate.
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Great into for how to recharge battery DIY. Hat down for this tool!
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Rechargeable batteries charging time; Is 9-1/2 hours charging time = or enough for 2300mAhr NiMH battery type and with 300mA nimh battery charger?
Battery type: 2300 mAh NiMH size AA rechargeable battery (2300mAh), Require: 9.2 hour(s) to be fully recharged with 300 mA charger, Fraction: 9 1/5 hours to be fully charged with 300 mA battery charger.
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How long to charge 1000mAh Ni-MH batteries size AAA with 500mA charger?
Comment from/about : alas | Permalink
Due to the existence of this charge current calculator there’s no need, in fact, for a manual charge current formula which I initially searched for! I’m making DIY my own manual battery charger using the formula for a charge current that I found on this page.
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Gaining information on AA’s battery charging time, I require exact four by 2300 aa batteries charging timing with 500mA charger, I have the SANYO brand batteries.
4x AA Battery type: 2300 mAh NiMH size AA rechargeable battery, Require: 5.5 hour(s) for AA battery charging time to be fully recharged with 500 mA charger. Fraction: 5 1/2 hours for aa battery charge time to be fully charged up with 500 Milli Ampere charger.
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Hi,
Thanks for your info, but I’m a bit confused on charging time.
Should be simple. Calculating for a 2000mAh NiCd battery (several sub-C in series). Charger is 400mA. Is the charge time simply 2000/400=5hrs, or do I always factor of 120% for time? If so, it would be 6hrs.
Your calculator shows 3.9 hrs. What am I missing.
Comment from/about : Rich | Permalink
Rich, that’s because when you compare nicd and nimh batteries, nicd take less time to be fully charged and, nicd type in general has also lower capacity. The chargers for nicd and nimh battery are slightly different too.
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I was wondering if there are any voltage restrictions to recharge the batteries since it only says the amps. thanks
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If battery is fully charged at that specific time, what is the current value of a battery? I had set to 9 hours with 300mA charger power output current in past, and adjusting to 9.2 hours from now on to 9h plus 30min. Results are below:
Battery type: 2300 mAh NiMH size AA rechargeable battery require 9.2 hour(s) to be fully recharged with 300 mA output current charger. Fraction: 9 1/5 hour(s) to be fully recharged with 300mA charger.
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Precise ma current to charging time for rechargeable batteries calculator. I made my own charger the other day and it works marvelous, hence help by the tool on this page to make it acurate.
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Hi ,
Thanks for writing such an interesting article. Its really good to know about the batteries in detail. Seriously do we realize how many things in your house that need batteries? Let’s count it, from the flashlight, cell phone, iPod, cameras, and many more. Knowing it should make us realize on how essential the presence of the batteries in our daily life. However, with that so many kinds of battery, which is generally different between one to another, sometimes we have some difficulties in finding the desired type.
Find the right batteries supplier is not hard if you check out batterystation.co.uk because this website provides the widest selection of batteries and you can choose the right battery based on the categories. You can get the procell batteries which available in several sizes and voltage. You also can find Duracell batteries that divided into duracell plus batteries and duracell ultra batteries. All of the batteries come with cheaper price because this website provides the discount batteries in bulk, wholesale, and retail quantities.
Thanks,
- Andrew Morales
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Great Site. Thank You. Our Dirt Devil Mop Vac batteries went dead after several years. I purchased 6 new 1800mAH sub C NiCDs on e-bay to build a new battery pack for it. After I pushed the “Buy It Now” button, I was dreading that the charger wouldn’t charge these higher capacity batteries to full potential. Your site set my mind at ease and calculated about 9.3 hours at 150mAH charge. I then wondered if the batteries would be damaged by leaving the Vac plugged in all the time when not in use.(our SOP) Your trickle charge calculations lead me to believe that I am charging at 4-times that rate. Is it a hazard or will the batteries just give out in a short period of time? Thanks in advance for your response.
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Couldn’t be better for battery charging time instructions for me!
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This converter is excellent for quickly finding out how to calculate “battery-pack” charging time I use for my RC radio.
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[...] charge to much less than given on the battery. also found a site to calculate the charging times Rechargeable battery charging time and mA current calculator | Convert to units measures. basics of calculating charging time is given on this [...]
Pingback from/about : Query on Sanyo batteries and Uniross charger - TechEnclave | Permalink
Thanks for great article and tool, Please help, What is the exact time, i use 4 AA uniross batteries 2500mAH, with songle charger, It output is ‘DC2.4V 100mA (AA*4)
Should i take output of charger as 100 or 400, please Answer. Will my charging time fast if i use only 2 batteries instead of 4 at a time.
Thanks
Comment from/about : Ashu | Permalink
CAN A NEWLY CHARGE SCREWGUN BATTERY BE LEFT IN A PLUGGED IN CHARGER UNTIL YOUR NEXT TIME USE OF THAT BATTERY? IS THAT BAD FOR THE BATTERY OR CHARGER?
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For example by devision 2500/70~35 Charging process will be same for 4 batteries or 2 batteries charged at the same time, 1 pair of batteries or 2 pairs together, in the charger giving same output to multiple batteries.
Elsewhere or in different chargers structured (such as made on your own) can give e.g. to 4 batteries charged together needed 2*35=70 hours time to be fully charged.
With most chargers it is clear that every pair of battery cells is placed in the charger in series for charging. Also, each pair gets same specific mA, as per your charger output used, when simultaneously charging 4 batteries/cells. Basically with one battery pair the charging current will also remain e.g. those 70 mA or your own specific. It is worth to mention that it’s advised to charge cells of the same mAh and to discharge all batteries prior the new charge so they all share the same capacity state, none will overcharge nor undercharge. Thanks cause this makes it quicker without calculating the time length with pencil on paper.
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